Telecommunication service providers are rapidly turning toward Ethernet for a cheaper and more suitable means to backhaul packetized data. Indeed, it is common for an Ethernet network to be used for providing frame relay emulation. In such a system, an ingress interworking function (IWF) sometimes receives a frame of a frame relay signal, strips frame relay header information, and encapsulates the payload of the frame into an Ethernet packet for transmission over an Ethernet network. However, the header information stripped from the frame contains information necessary for recreating the frame at the egress IWF of the Ethernet network.
For example, frame relay congestion notifications, such as Forward Explicit Congestion Notification (FECN) and Backward Explicit Congestion Notification (BECN), are typically transmitted via frame relay headers. Upon receiving such a notification, a node might reduce its transmission rate in an effort to alleviate the congestion until the status of the FECN/BECN indicates that the congestion is no longer present. Unfortunately, there is no standard to communicate FECN/BECN across the interworking function at the edge of an Ethernet network. Unless techniques are developed to propagate FECN/BECN through the Ethernet network, the FECN/BECN information is lost when the ingress IWF strips away the frame relay header information.
Thus, a heretofore unaddressed need exists in the art for propagating frame relay congestion notifications, such as FECN or BECN, through a packet network without violating applicable protocols, such as Ethernet protocols.